Apparatus and method for the observation of flames



Jan. 29, 1963 A. L. cAzALAs 3,075,577

APPARATUS ANO METHOD EOE TEE OBSERVATION OE FLAMES Filed July 2O. 1959 ATTURNEY United States Patent @ffice 3,075,577 Patented Jan. 29, 1953 3,075,577 APPARATUS AND METHOD FOR ThE BSERVATIN OF FLAMES Andr Louis Cazalas, Paris, France, assigner to Compagnie pour la Fabrication des Compteurs et Materiel dUsines a Gaz, Montrouge-Seine, France, a corporation of France Filed July 20, 1.959, Ser. No. 82%,3SS Claims priority. application France .'iuly 22, 1953 4 Cllaiu'ns.l (Cl. 158-122) This invention relates generally to an improved method and means for ame observation, and more particularly, to a new method and means for observing flame configuration within furnaces, boilers and the like, and for facilitating this observation by increasing the contrast between the flame and the flame background.

Those skilled in the furnace and boiler arts appreciate the diiculties of observing the conguration of the flame utilized in the firing of these devices. They also know that While such observation is extremely desirable to the end that the firing operation be made as efficient as possible, the observation of the flame within a furnace or boiler in the prior art has not been entirely satisfactory for a number of reasons. For example, the ames fed by city gas, natural gas, hydro-carbon and other fuels often are scarcely visible, since their characteristic color is not distinct and their brightness is weak. Flame observation is further impeded in that the light from the walls of the furnace or boiler is corriparable to the flames, and the differences in color between the walls and the flames are slight.

Accordingly, it is a general object of this invention to provide a new and improved method and meansv for facilitating the observation of flames, suchv as those used in the ring of furnaces or boilers.

It is another object of this invention to provide a new method and means for observing the configuration of a flame within a furnace or boiler by incorporating a metallic salt into the fuel supply for the flame. Thus it is a feature of this invention that the flame is colored by the introduction of the metallic salt into the fuel supply such that the light emitted by the flame contains emission rays characteristic of the added metal. In accordance with one specific illustrative embodiment of the invention a saline solution, such as lsodium chloride, is mixed with the fuel to give the flame a yellow color characteristic of sodium rays. In addition to this color change, the brightness ofthe flame is increased and therefore the flame contrasts more sharply .with the background walls that are being heated.

' It is a further object of this invention to facilitate the viewing or observation of the flames which have been treated in the above-described manner by providing spe'- cial optical means at an opening'in the furnace wall, Thus in accordance with further features of the invention, a television camera may be used to observe flame conguration within the furnace or boiler, and the flame is rendered visible in white on a gray or black background, while prior to the introduction of the metallic salt such flame would effectively be undetectable due to its lack ofl contrast with the furnace wall background.

It is a still further object of this invention to enhance the observation of the flame by positioning an optical filter between the llame and the television camera or the eye of the observer. Thus, for example, an optional filter of the interferential type may be used to increase the contrast of a televised image or its visibility to the eye, since it serves to pass the emission rays of the ame colored by the metallic salt and to absorb the other parts of the spectrum, and in particulaigthe extreme red end of the spectrum.

The above and other lobjects and features of the invention are pointed out with particularity in the claims annexed to and forming a part of this specification. For a better understanding the invention, however, its advantages and specific object attained with its use, reference is vhad to the accompanying drawings and descriptive matter in which are shown and described several illustrative embodiments of lthe invention.

In the drawing:

FIGURE 1 illustrates an example of apparatus for injecting a metallic salt into the fuel in accordance with the invention;

FIGURES 2 and 3 show two illustrative arrangements for positioningV a television camera with respect to the furnace to facilitate observation of the burners and flame conguration therein;

FIGURE 4 shows one illustrative optical arrangement for viewing the interior of the furnace by means of the television camera; and

FIGURE 5 illustrates another illustrative optical arrangement for viewing the interior of the furnace by means of a television camera.

Referring now to the drawing7 and more particularly to FIG. l thereof,A there is shown a preferred embodiment of apparatus for supplying a mixture of fuel and a metallic salt to a burner. An opening 10 in the wall of a boiler I2 is provided with a plurality of parallel plates or fins 14 for defiecting the fuel supplied through the pipe line 1,6. It is contemplated that the fins I4 may also be arranged in a radial manner to increase the turbulence of the flame.

Advantageously the burner may be fed by a combustif ble gas such as city gas, natural gas, etc., or by a mixture'of air and powdered carbon which empties through the orifice I8 at the outlet of the pipe line I6. A casing 26 is provided at the boiler opening 10 to fully enclose or surround the pipe line orifice I8. The casing 26 is fed from a supply of secondary air by a conduit 22 for enabling a metallic salt to be added to the fuel within the chamber defined by the casing 20.

One advantageous arrangement for supplying the metallic salt to the conduit 22 is shown by the apparatus directly below the conduit 22. 'I'his apparatus comprises a valve 24 which is connected to a compressor 26 that serves to supply air under pressure to the cylindrical member 28. Cylindrical member 28 is terminated by the fitting 30, whichopens into a chamber 32 joined to the conduit 22 by the pipe 34 positioned forward of the valve 24.

Within the cylindrical member 28 there is provided a concentrically located conduit 36 that empties into the fitting 36 and this conduit 3 6 is in fiuid communication 'with the lower part of the chamber 32 and with a storage tank 38 such that the levels of the saline solution within the storage tank 38 and the chamber 32 are maintained at a common level. A container 47th` having tlierewithin a saline solution, such as the solution of sodium chloride, is provided abovethe storage tank 3S andY is adapted to be in fluid communication therewith by means of the conduit 42. Advantageously, afloat 44 having a needle valve 46 is regulated so that the saline solution from the container 4S is fed into theV storage tank 3S at a level slightly below the level of the horizontally positioned conduit 36 when the compressor 26 is not operating and when the conduit 22 is not discharging.

In the operation of the apparatuses shown in FIGURE l, theA compressor 26 supplies the fitting 30 with a jet of air, which by pump action creates a flow inthe cylindrical member 28 and effects suction in conduit 36 and pulverization of droplets of the saline solution. The fine droplets are carried along into the conduit 22, while the largest droplets fall to the bottom of the chamber 32 back into the solution for use in the further operation of the system. The droplets within the conduit 22 are evaporated by the secondary air which runs therethrough, and therefore the fuel mixture charged with the metallic salt is provided for the combustion of the gas at the burner.

Those skilled in the art will appreciate that many other types of apparatus may be used for incorporating the metallic salt into the fuel; for example, a device can be connected directly to the pipe line lo carrying the combustible gas in lieu of the conduit for secondary air 22, as for example, a pulverizer, a pump injector, a filter, or a cylinder impregnated with the saline solution, to produce the san-ie result.

As a result of mixing the saline solution with the gas, in the manner described above, the flame at the burner is provided with the characteristic color of the metallic salt and in accordance with a feature of this invention, the flame at the burner may more easily be viewed to determine its configuration to the end that the furnace may be adjusted for maximum efficiency of operation.

Those skilled in the art appreciate that boilers or furnaces generally have a parallelopiped form and that in one type of furnace, the burners may be arranged in the direction of the axis but are slightly displaced so that there is produced at the center a swirling movement to increase the turbulence therewithin. in this type of furnace, as illustrated by the FIGURE 2 in the drawing, an opening may be provided for a television camera at the position where one of the walls of the burner is found to provide a substantially horizontal member 5S. The burners Sti, of which only four are shown in FIG. 2 to simplify the drawing (one in each corner), may be observed with the aid of the television camera 52 adjacent the wail opening Sti. The television camera 52 is furnished with a periscope device 5d which advantageously is placed within a sheath that may be cooled by a refrigerated liquid as described in greater detail hereinbelow. The angle of the field of the periscope 5d is determined to encompass all four burners 5@ and therefore this arrangement permits a total observation of the four burners positioned at the corners of the furnace.

lin another type of furnace, as shown in FGURE 3 of the drawing, the burners of? are all arranged in a lower portion of a wall of the furnace 62. With this arrangement the television camera 52 is provided at an opening 6d in the wall of the furnace opposite the wall having the burners dfi, and at a height selected so that,

in the television image, the burners do not conceal each other.

lt also will be appreciated that if any burner in particular is desired to be viewed so that its iiame conguration may be observed, the camera may be positioned at a place chosen to best provide local observation of this burner.

FIGURES 4 and 5 illustrate two examples of embodiments of specific means for providing viewing of the burners by a television camera. in FIG. 4, the camera 52 has its objective 66 mounted directly behind a transparent window dS positioned in the opening of the furnace wall 72. Advantageously a current of cold air, supplied under pressure, is circulated in the ducts 7d to both maintain the window 68 at a low temperature and further, to avoid a deposit on the window of cinders and dust which are carried across the protective screen 76. An optical filter 73 is positioned between the window 63 and the television camera objective 66 so that only the characteristic rays emitted by the metal of the saline solution incorporated into the combustible fuel are transmitted to the television camera, while the other rays of the spectrum are prevented from being transmitted to the television camera. ln this manner the viewing of the flame configuration is greatly enhanced, for the flame then can easily be observed on the television screen due to its sharp contrast in color and brightness with the coloring and brightness of the furnace wall background.

ri'he arrangement of FIG. 5 includes a television carn- 'era tl which is positioned adjacent an opening S2 in the furnace wall A periscope device 2d is positioned within the opening 82 and advantageously the periscope device is provided with an envelope fe which may be of stainless steel, having a transparent window fifi at one end thereof within the furnace and a further transparent window 9i) at the other end thereof adjacent the television camera The periscope device d4 is cooled, in accordance with one embodiment of the invention, by means of a refrigerated liquid distributed throughout its interior, said refrigerated liquid being supplied to and removed from the eriscope device by means of the conduits 92 and 94. Within the periscope Sli, there is provided an optical system which in the example of FlG. 5 comprises the lenses 96, the prism 9S and the filter fdd. By this arrangement, the configuration of the darne or flames within the furnace may be viewed at a remote point and with the flame configuration sharply defined on the viewing screen as a result of cooperative effects of the saline solution in the combustible fuel and the filter in the optical system.

There have been shown and described several illustrative methods and means for facilitating the observation of the flame within a furnace by increasing the contrast between the flame and the furnace background and by enabling the fiame to be viewed at a point remote from the furnace. Those skilled in the art will readily appreciate that the various arrangements shown and described above are merely illustrative of the principles of the invention and that modifications may be made without departing from the principles and spirit of the invention, and that the true scope of the invention is defined by the appended claims.

What is claimed as the invention is:

l. A system for providing remote indications of the ame configuration within a furnace comprising a furnace enclosure, at least one burner positioned at an opening in said furnace enclosure, means for feeding a continuous supply of fuel to said burner to provide a fiarne within said enclosure, means for introducing a controlled amount of inorganic saline solution to said fuel for increasing the specific luminosity of said iiame characterized by the spectrum emission of said solution, indicating means for enabling the remote viewing of said flame comprising a television camera positioned at a further opening in said furnace enclosure, and filter means positioned between the flame and the television camera selectively transparent to said characterized spectrum emission of said flame for enabling the configuration of the flame to be distinguished from the background color of said furnace enclosure whereby the flame configuration may be viewed at a television receiver located at a point remote from said furnace.

2. A system for providing indications of ame configuration within a furnace comprising a furnace enclosure, 'a plurality of burners positioned at a plurality of spaced-apart openings in said furnace enclosure, means for feeding a continuous supply of fuel to said burners to provide a flame within said enclosure, means for introducing a controlled amount of sodium chloride solution to said fuel for increasing the sodium luminosity of said flame characterized by the specific spectrum emission of sodium, optical means positioned at a further opening in said furnace enclosure for enabling the remote vviewing of the llame configuration within said furnace, and filter means positioned between the fiame and said optical means selectively transparent to the sodium spectrum emission of said iiame for enabling the conguration of the ame to be distinguished from the background color of said furnace enclosure.

3. A method of providing remote indications of the flame configuration within a furnace enclosure comprising the steps of feeding a continuous ysupply of fuel to a burner extending through a wall of the furnace enclosure to provide a flame, mixing a saline solution with the fuel before it is fed to the burner to canse the ame to be colored in an identiable manner, positioning a television camera at an opening in the furnace enclosure, and positioning a filter selectively transparent to the identifiable color of the ame between said television camera and said arne for enabling the configuration of the flame to be distinguished from the remainder of the furnace interior and viewed Iat a television receiver located remote xof a point from the furnace.

4. A method of providing remote indications of the ame configuration within a furnace enclosure comprising the steps of feeding a continuous supply of fuel to a burner extending through a wall of the furnace enclosure to provide a ame, mixing a saline solution with the fuel before it is fed to the burner to cause the flame to be colored in an identifiable manner, providing a viewing yopening in a wall of the furnace 6 enclosure, and positioning a filter selectively transparent to the identifiable color of the flame in said viewing opening for enabling the configuration of the arne to be distinguished fro-rn the remainder of the furnace interior and viewed at a point remote from the furnace interior.

References Cited in the file of this patent UNITED STATES PATENTS 2,054,382 Larsen et a1. Sept. 15, 1936 2,592,847 Babicz Apr. 15, 1952 2,714,833 Gilbert Aug. 19, 1955 2,753,753 Gardiner July l0, 1956 2,857,801 Murray Oct. 28, 1958 2,858,729 Keyes Nov. 4, 1958 OTHER REFERENCES in Power Stations, Mechanical Engineering Magazine, December 1951; pages 1008, 1009. 

1. A SYSTEM FOR PROVIDING REMOTE INDICATIONS OF THE FLAME CONFIGURATION WITHIN A FURNACE COMPRISING A FURNACE ENCLOSURE, AT LEAST ONE BURNER POSITIONED AT AN OPENING IN SAID FURNACE ENCLOSURE, MEANS FOR FEEDING A CONTINUOUS SUPPLY OF FUEL TO SAID BURNER TO PROVIDE A FLAME WITHIN SAID ENCLOSURE, MEANS FOR INTRODUCING A CONTROLLED AMOUNT OF INORGANIC SALINE SOLUTION TO SAID FUEL FOR INCREASING THE SPECIFIC LUMINOSITY OF SAID FLAME CHARACTERIZED BY THE SPECTRUM EMISSION OF SAID SOLUTION, INDICATING MEANS FOR ENABLING THE REMOTE VIEWING OF SAID FLAME COMPRISING A TELEVISION CAMERA POSITIONED AT A FURTHER OPENING IN SAID FURNACE ENCLOSURE, AND FILTER MEANS POSITIONED BETWEEN THE FLAME AND THE TELEVISION CAMERA SELECTIVELY TRANSPARENT TO SAID CHARACTERIZED SPECTRUM EMISSION OF SAID FLAME FOR ENABLING THE CONFIGURATION OF THE FLAME TO BE DISTINGUISHED FROM THE BACKGROUND COLOR OF SAID FURNACE ENCLOSURE WHEREBY THE FLAME CONFIGURATION MAY BE VIEWED AT A TELEVISION RECEIVER LOCATED AT A POINT REMOTE FROM SAID FURNACE. 